Western Water Q&A: Jayne Harkins’ duties include collaboration with Mexico on Colorado River supply, water quality issues

Jayne Harkins, the U.S. Commissioner of the International Boundary and Water Commission. (Image: IBWC)

For the bulk of her career, Jayne Harkins has devoted her energy to issues associated with the management of the Colorado River, both with the U.S. Bureau of Reclamation and with the Colorado River Commission of Nevada.

Now her career is taking a different direction. Harkins, 58, was appointed by President Trump last August to take the helm of the United States section of the U.S.-Mexico agency that oversees myriad water matters between the two countries as they seek to sustainably manage the supply and water quality of the Colorado River, including its once-thriving Delta in Mexico, and other rivers the two countries share. She is the first woman to be named the U.S. Commissioner of the International Boundary and Water Commission for either the United States or Mexico in the commission’s 129-year history.

The IBWC, whose jurisdiction covers the 1,954 miles of border from San Diego to the Gulf of Mexico, is responsible for applying the boundary and
he United States and Mexico, and settling differences that may arise in their application.

The IBWC is recognizable to many people as the implementing body for the additions to the 1944 U.S.-Mexican Water Treaty on the Colorado, Rio Grande and Tijuana rivers known as Minutes. In 2017, the latest addendum, Minute 323, built on previous agreements that specified reductions in water deliveries to Mexico off the Colorado River during a shortage and allowed Mexico to store water in Lake Mead, the nation’s largest reservoir which sits near Las Vegas.

The New River, a contaminated waterway that flows north from Mexico, spills into the Salton Sea in southwestern California’s Imperial Valley. Transborder pollution is among Jayne Harkins’ priorities as U.S. IBWC Commissioner. (Image: U.S. Bureau of Reclamation)

There are other issues, as well. Transborder pollution – from the New River spilling into the Salton Sea and from the Tijuana River fouling San Diego County beaches – is on her radar. Last year, the San Diego Regional Water Quality Control Board sued the U.S. section of the IBWC, claiming it is violating the Clean Water Act by not monitoring or stopping the untreated waste flowing to the Pacific Ocean from the Tijuana River that has caused beach closures in San Diego County.

Harkins, who lives in El Paso, Texas, spoke recently to Western Water about her new mission, transborder pollution and addressing Colorado River shortages with Mexico. The transcript has been lightly edited for space.

You are the first woman to be selected as IBWC commissioner. Do you see that as a significant accomplishment?

Yeah, I do. It is [significant] but I wish it weren’t. It should have happened a long time ago from my perspective. For me, you just plow on and get work done.

What is the significance of the IBWC and how its mission affects the various stakeholders?

We started as the International Boundary Commission and, of course, that is more straightforward. They work to demarcate the boundary, [and] maintain our boundary monuments.

Jayne Harkins (seated, far left), as executive director of the Colorado River Commission of Nevada, was one of the signers in 2017 of domestic agreements that were part of Minute 323, the addendum to the 1944 U.S.-Mexican Water Treaty. (Image: U.S. Bureau of Reclamation)

In 1944, of course, we got the treaty with Mexico that went beyond boundary stuff. That is what distributed waters between the United States and Mexico on the Colorado River. A part of that treaty authorized the joint construction and operation of international storage dams on the Rio Grande, and there is some discussion on a preferential solution to the issue of border sanitation problems.

I think a lot of what IBWC can do in both the U.S. and Mexico is bring all the stakeholders together into binational meetings to talk about the data we have, what are we lacking and then try to resolve issues.

What are your priorities as commissioner?

My priority is border sanitation. We have a number of areas with border sanitation issues and that’s one to try and figure out and see what we can do. Also, we have our treaty water deliveries and water quantity and quality responsibilities, depending on what the minutes require. We have those pieces that we need to make sure get done. We have got infrastructure issues on some of our dams and we just need to be operating and maintaining older infrastructure and make sure we are repairing and replacing as needed.

What is the IBWC’s role in water quality issues?

We are coordinating with others because there are some things that we can’t do that others can, and so we are trying to bring a coordinated effort among the federal U.S. entities. With Mexico, it’s what are the appropriate entities, federal and state, that they have to have. Each one of these is a local issue and we’ve got to bring in the local stakeholders because they have an interest as well. Some solutions may include infrastructure on both sides of the border. A number of studies regarding infrastructure improvements have been completed or are underway. We are working with local, state and federal agencies, as well as Mexico, to address the Tijuana River sanitation issue in a cooperative manner.

This has been ongoing for a long time. As I looked at it, I’m like, “Are things better than they were?” If you look at the data, even New River stuff [the New River flows from Mexico into California’s Imperial Valley and toward the Salton Sea], it’s much better than it was 20 years ago. If you look at the numbers overall, it’s not good enough. It’s not like the discharges meet U.S. standards and that’s what people in the U.S. are looking for. We are trying to help be a convener of folks to make sure we know what the data looks like, to make sure we know fact from fiction and bring people together who can perhaps bring some money to this and work with Mexico to see who can do what parts.

The water quality issues on the Colorado River are outlined in Minute 242 as related to salinity requirements. Minute 323 established a Salinity Work Group to minimize the impact of Minute 323 activities on salinity and to undertake cooperative actions like modernizing salinity monitoring equipment.

How is the IBWC involved with drought planning efforts?

Colorado River water released from Morelos Dam, along the border with Mexico, flows downstream into the Colorado River channel in March 2014 to benefit the environment as part of the cooperative measures agreed to by the United States and Mexico under Minute 319. (Image: U.S. Bureau of Reclamation)

We are not specifically engaged in the Lower Basin Drought Contingency Plan, but we are very interested in it and monitoring it and checking in with folks about what’s going on. Mexico is very interested because they have agreed to sharing shortages when the Lower Basin is in shortage. If there is a Lower Basin Drought Contingency Plan, Mexico has their Binational Water Scarcity Plan and they would take some additional reductions. So from the standpoint as to how we implement Minute 323 and what we need to do with sharing information with Mexico, that’s our part of the involvement.

The Binational Water Scarcity Contingency Plan is essentially how the DCP would be applied to Mexico.

What’s the status of Minute 323 implementation?

There are a number of conservation projects in Mexico that are wrapping up. We are involved in the verification that they got constructed. We will work with Mexico on the quantity of water that’s being conserved. As construction gets done, those projects are funded by some of the U.S. stakeholders, and we move that money over to Mexico so they can pay the contractors.

A recent report provided findings of the 2014 pulse flow of more than 100,000 acre-feet of water into the riparian corridor of the Colorado River Delta implemented under Minute 319. How will that inform future efforts?

We learned many things about water delivery methods, infiltration, irrigation techniques and groundwater – information that will guide our Minute 323 environmental work. This report provides solid scientific information about our restoration efforts. The findings will help us apply environmental water more effectively in the future.

FromYale 360 (Jim Robbins). Here’s an excerpt click through for the photos and to read the whole article:

The Colorado River has been dammed, diverted, and slowed by reservoirs, strangling the life out of a once-thriving ecosystem. But in the U.S. and Mexico, efforts are underway to revive sections of the river and restore vital riparian habitat for native plants, fish, and wildlife. Fifth in a series.

From the air, the last gasp of the Colorado River is sudden and dramatic. The pale green river flows smack into the Morelos Dam on the U.S.-Mexico border, and virtually all of it is immediately diverted into a large irrigation canal that waters a mosaic of hundreds of fields — alfalfa, asparagus, lettuce, and other vegetables, their vivid green color clashing against the sere desert. The slender thread of water that remains in the Colorado’s channel continues to flow south, but is soon swallowed up by a sea of sand, far short of its delta, which lies 100 miles farther on.

The Colorado River once surged through the delta during high flows, carrying so much water at times that shallow draft steamboats chugged hundreds of miles up the river into the U.S. with loads of freight. The water in the delta nourished a vast fertile landscape, a fitting end to a river known as the Nile of North America.

“The river was everywhere and nowhere,” the naturalist Aldo Leopold wrote during a 1922 canoe trip to the delta, describing the waterway as it ebbed, flowed, braided, and stalled into pools, nourishing a rich and diverse ecosystem of “a hundred green lagoons,” a “milk and honey wilderness” with thick stands of cottonwoods and willows that provided habitat for hundreds of species of birds. The delta’s marshes, mudflats, and white sand beaches were home to clapper rails, bitterns, mallards, teal, and clouds of egrets.

Bobcats, puma, deer, and wild boar wandered the delta’s forests. Leopold was searching for the jaguar that roamed there, but didn’t see any…

Morelos Dam. Photo credit American Rivers.

As a natural river, before it was dammed, the Colorado was a massive, dynamic waterway. It flowed from elevations above 14,000 feet in the Colorado Rockies, then dropped to sea level, which meant that it moved at high water with tremendous force, liquid sandpaper carving out red rock canyons. It flooded the desert plains, carving new channels and braids with every inundation. When it receded, it left behind a mosaic of fecund marshes, wetlands, and ponds.

In its natural state, the Colorado had more extreme flows than any river in the U.S., ranging from lows of 2,500 cubic feet per second in the winter to 100,000 cubic feet per second in the summer. In 1884, an all-time historical peak flow reached 384,000 cubic feet per second in Arizona.

But extreme flows are too capricious to support a civilization, so over the past century or so humans have built a network of expensive dams and reservoirs, pipelines, canals, flumes, and aqueducts to tame and divert the flow. Yet these projects also strangled the life out of a once-thriving ecosystem. By design, the river will never again function as a free-flowing stream.

Now, however, experts and environmentalists are rethinking this technological marvel of a river, and looking at ways a natural Colorado can flourish — to some degree, and in some places — with the permission of the engineers. One of those places is in the delta.

The water that flowed in the once-lush delta has been replaced by sand, and the cottonwoods and willows have surrendered their turf to widespread invasive salt cedar and arrowweed. Without the river and its load of nutrients, marine productivity in the Gulf of California — where the Colorado River once ended — has fallen by up to 95 percent. But despite the dismal forecast for the future of water on the Colorado, some conservationists are hoping to return at least a portion of the delta to its former glory.

“We are trying to restore a network of sites that creates a functional ecosystem,” said Francisco Zamora, who manages the project for the Sonoran Institute. “We’ve acquired water rights, but use them for habitat instead of cotton or wheat.”

The delta is one of a disconnected series of restoration projects that government agencies, local groups, and environmental organizations are undertaking along the Colorado. Numerous efforts are focused on tributaries to the main stem of the river, seeking to enhance resiliency by increasing the flow of water and protecting and restoring riparian habitat for fish and other wildlife.

For example, a coalition of groups — including state agencies, nonprofits, and the Arizona cities of Buckeye and Agua Fria — have been removing invasive salt cedar, planting native species, and building levees to reclaim a 17-mile stretch of the Gila River. Invasive salt cedars are a region-wide problem on the lower Colorado, with a single tree sucking up 300 gallons a day. The invasive forest on this stretch of the river uses enough water to serve 200,000 households.

In the upper basin, meanwhile, a number of groups and local landowners are working to restore a 15-mile-long floodplain with globally significant biodiversity on a narrow section of the Yampa River, another Colorado tributary. Called Morgan Bottom, the section has been damaged by deforestation and poor agricultural practices, threatening bald eagles and greater sand hill cranes, as well as a rare riparian forest of narrowleaf cottonwood and red osier dogwood.

But there are limits to how natural the Colorado River can become, especially along the river’s main stem. “We should not kid ourselves that we are making it natural again,” said John Fleck, the director of the University of New Mexico’s water resources program and the author of a book about the restoration of the Colorado. “We are creating an intensively managed system to mimic some nature because we value it.”

Because of the Colorado’s extensive infrastructure, serious disruption of the river’s ecology is inevitable.

Indeed, some of the remaining naturalness on the Colorado is, paradoxically, because of the human-made system. “The geography of the Colorado gives it hope because L.A. and southern California, which everybody loves to hate, guarantee that a lot of water stays in the system through the Grand Canyon,” says Jack Schmidt, a professor at Utah State University and a member of the Colorado River Research Group. “The best friend endangered fish ever had in the Colorado River Basin is that giant sucking sound” of California withdrawing water.

Widespread protection efforts are focused on native fish in the Colorado. The river once was home to an unusual number of endemic fish. But dams, irrigation, and the introduction of bullhead, carp, and catfish did them in. While the upper basin still has 14 native fish species, the lower basin, according to one study, “has the dubious distinction of being among the few major rivers of the world with an entirely introduced fish fauna.”

The Colorado pike minnow — something of a misnomer for a fish that historically grew to 6 feet in length and weighed up to 80 pounds — once swam through the entire system from Wyoming to Mexico. It is now listed as endangered, with two distinct populations remaining in the upper Colorado and the Green River.

The humpback chub lived in various canyon sections, and though once seriously endangered, it has fared better in recent years through transplantation efforts, growing from 2,000 to 3,000 fish to 11,000. Officials say it may soon be taken off the endangered list.Beginnings. Photo: Brent Gardner-Smith/Aspen Journalism

Razorback suckers, once common, are now rare. The bonytail, a type of chub that is one of North America’s most endangered fish, no longer exists in the wild. A handful of these fish exist in hatcheries, and attempts are underway to restock them in the river throughout the basin.

Because of the Colorado’s extensive infrastructure, serious disruption of the river’s ecology is inevitable. Dams trap most of the river’s sediment in reservoirs, which means there is no material to rebuild beaches, sandbars, and important fish habitat downstream.

Dams also deprive the river downstream of nutrients, such as phosphorous and nitrogen, and stratify water temperatures. The native fish in the Colorado adapted to a wide range of temperatures, from cold to very warm. They also evolved to tolerate high flood flows along with extremely dry periods. Now, the water is cold in the summer for miles below the dams, and the humpback chub and other fish that had adapted to a range of water temperatures and flows suffer.

Something called hydro-peaking also has had serious impacts on the food web. Dams generate power according to demand. As people come home from work and switch on the stove, air conditioning, and lights, demand soars and dams release more water to produce power. “Prior to the construction of dams, there were almost no major daily changes in river levels,” said David Lytle, a professor of integrative biology at Oregon State University. When fluctuations in water levels occur, they “can interrupt the egg-laying practices of some species. It’s a serious problem.”

Insects lay their eggs just below the water level, and if levels drop rapidly it can dry them out. A recent study found that below the Hoover and Glen Canyon dams, there was a complete absence of stoneflies, mayflies, and other species — insects that are vital food for fish, bats, birds, and other creatures.

Because of the ecological effects of the Glen Canyon Dam, the Grand Canyon stretch of the Colorado is one of the least productive sections of river in the world. The Colorado here will always be highly unnatural, a novel, human-created ecosystem with some natural elements.

Today, there is a large and growing backlash against dams in America and elsewhere as the immense damages they have inflicted on rivers become manifest. Few dams, though, are as reviled as the Glen Canyon, which was built in 1963 and took 17 years to fill Lake Powell.

Before the Glen Canyon was dammed, those who saw it say it was not unlike the Grand Canyon, with towering walls of red, tan, and ochre. Early Native American sites were plentiful. Environmental activist Edward Abbey decried the dam, and in his novel the Monkey Wrench Gang fantasized about using houseboats packed with explosives to blow it up. In 1981, members of Earth First!, a radical environmental group with a connection to Abbey, rolled a black plastic “crack” down the face of the dam to symbolize its demise.

Changes in the northeastern reaches of Lake Powell are documented in this series of natural-color images taken by the Landsat series of satellites between 1999 and 2017. The Colorado River flows in from the east around Mile Crag Bend and is swallowed by the lake. At the west end of Narrow Canyon, the Dirty Devil River joins the lake from the north. (At normal water levels, both rivers are essentially part of the reservoir.) At the beginning of the series in 1999, water levels in Lake Powell were relatively high, and the water was a clear, dark blue. The sediment-filled Colorado River appeared green-brown. To see the complete series go to: earthobservatory.nasa.gov/WorldOfChange/LakePowell. Photos via NASA

Removing the dam was part of the reason the Glen Canyon Institute was formed, but activists have now dropped that idea, says Rich Ingebretsen, a Salt Lake City physician who founded the group. Today, he advocates draining Lake Powell to fill Lake Mead, which is downstream and where the need for water is by far the greatest. The “Fill Mead First” campaign would restore a free-running Colorado River to what was once Lake Powell.

“You’d get much of Glen Canyon back,” said Ingebretsen. “A free-flowing river through the Grand Canyon means you’d restore the river — riparian zones, animals that belong there, a beautiful canyon with arches and bridges and waterfalls. Much of that would come back very quickly.” There would also be increased water in the river, he says, because so much of the Colorado is now lost from Lake Powell; scientists estimate that the lake loses three times Nevada’s allotment of water because of evaporation. As levels in Lake Mead drop due to prolonged drought, a growing number of people are taking this idea more seriously.

Paradoxically, two of the Colorado River’s most important wetlands for wildlife are the product of runoff from irrigated farm fields — and are now at risk from a changing climate and agreements to reduce water use.

In the Sonoran Desert of northwestern Mexico, the 40,000-acre La Cienega de Santa Clara wetland was inadvertently created in the 1970s when U.S. officials built a canal to dispose of salty wastewater from agricultural fields in Arizona. As the water began spilling into the desert, myriad forms of life began to appear. Now its cattail-studded marshes and mudflats are considered one of the most important wetlands in North America, home to 280 species of birds — including the endangered Ridgeways rail — on what was once hard-baked desert.

Meanwhile, in California, the Salton Sea was once a shallow inland lake whose levels routinely fluctuated. In 1905, an effort to increase Colorado River flow into the Imperial Valley led farmers to allow too much river water into their irrigation canal, overwhelming their system; for two years the water poured into the 35-mile-long, 15-mile-wide Salton Sea and expanded it.

But as less water becomes available to agriculture and rising temperatures cause more water to evaporate, scientists are concerned that these wetlands will dry and shrink faster than they already have. A 2003 agreement, for example, allows agricultural water in the Imperial Valley to be sent to San Diego for municipal uses. That could cause water levels in the Salton Sea to drop by more than 40 percent, dramatically reducing bird habitat and increasing toxic dust because wetlands would dry out. Local, state, and federal officials have devised a plan — still not fully funded — to restore 15,000 acres of wetlands, at a cost of more than $700 million.

The largest project to restore some semblance of nature to the Colorado River, though, is in the delta. An unusual agreement in 2012 between the U.S. and Mexico, called Minute 319, mandated that the two countries would provide water and funding to revive sections of the delta and release a one-time pulse of 105,000 acre-feet to again connect the river to the delta temporarily. Scientists would then study the effects.

In 2014, for the first time in decades, the river flowed again in Mexico — for eight weeks. San Luis Rio Colorado — once a Colorado River town, but now a dusty desert settlement — became a river town for two months, to the delight of locals, many of whom had never seen the river. The pulse offered a glimpse of what reclamation efforts might look like. “It gave us an idea of how the river behaves, and the best sites for restoration,” said Zamora.

Martha Gomez-Sapiens, a monitoring team member and postdoctoral research associate in the UA Department of Geosciences, stands on a riverbank next to willows and cottonwoods that germinated as a result of the pulse flow. (Photo: Karl W. Flessa/UA Department of Geosciences)

Minute 319 and its 2017 replacement, Minute 323, have funded the restoration of sections of the river. A group of nonprofits — including the National Audubon Society, the Sonoran Institute, The Nature Conservancy, and a Mexican group called Pronatura Noroeste — is working on a project called Raise the River to revive a significant swath of the delta.

In 2008, the group secured rights to 1,200 acres along the desiccated river channel. Since then, local residents have torn out acres of salt cedar and planted irrigated fields of cottonwood, willow, and other endemic species — more than 200,000 trees in all. A small supply of water mandated by the treaty, along with excess water that flows off of irrigated fields, have been dedicated to the restoration.

On a recent visit, I joined Zamora and botanist Celia Alvarado on a short boat ride to Laguna Grande, a 6-mile section of restored river and estuary. We skimmed across still water the color of weak tea, minnows darting away from our paddles. Thick groves of cottonwoods and willows lined the river. Zamora remarked that bobcats and beaver lived there now, along with blue grosbeaks and yellow-billed cuckoos. “Impacting the target species is key,” he said.

And what about the jaguar? I asked. It has not returned, he said. Will it come back?

“Yes,” said Zamora, smiling. “Someday. If they allow me to introduce them.”

Several tributaries of the Colorado River get their start in the crags of the Central Colorado mountains. Storied rivers: Blue, Eagle, Roaring Fork and the powerhouse Gunnison. They’ve all faced the footstep of humankind. The mines dotting the slopes, hay fields, ranching, orchards and cornfields bear witness and are now part of the allure of the high country. Folks cast a line, shoot rapids and enjoy the scenery of those waterways.

On September 27, 2017, the International Boundary and Water Commission, United States and Mexico inked Minute 323, the amendment to the 1944 United States-Mexico Treaty for Utilization of Water covering operations on the Colorado, Rio Grande and Tijuana rivers. (The Rio Grande is another of Central Colorado’s contributions to the Western U.S. economy.)

An important part of Minute 323 are environmental flows for the Colorado River Delta. Most everyone knows the river doesn’t reach the sea any longer. Environmental streamflow was initiated under Minute 319 signed by then Secretary of Interior Ken Salazar.

Young girl enjoying the river restored temporarily by the pulse flow March 2014 via National Geographic

In March 2016 a diverse group of conservationists, biologists, irrigators and government officials effected a release of 100,000 acre-feet of water from Morelos Dam into the dry Colorado River Delta. There was a line of vehicles racing point to point along the river to witness the river’s front. At San Luis Rio Colorado, most of the residents went down to the river to celebrate the return of the river although many had no memory of running water in the sandy channel.

There was a great deal of success from channeling some of the streamflow to restoration sites in the Delta. Within weeks, new growth sprouted – cottonwoods and willows. Much of the diverted water served to replenish groundwater supplies. Wildlife immediately started using the habitat.

There probably won’t be a repeat of the Colorado River once again reaching the sea. The environmental flows in Minute 323 are planned to be set to work in the restoration of the Delta. It was great to see the river reach the sea but the conservationists want to concentrate flows like irrigators do for maximum yield.

Another feature of the deal allows Mexico to store water in Lake Mead to better manage their diversions for agriculture. The U.S. is also helping to rebuild and upgrade Mexican infrastructure. Under Minute 319, Mexico was allowed to continue storing water, and that water was used for the pulse flow. The idea is that greater efficiency in Mexico will lead to more storage in Lake Mead.

Currently, Arizona, California and Nevada are working on a drought contingency plan to stave off a shortage declaration in Lake Mead. Arizona’s Colorado River allocation takes a big hit under a declaration. Mexico’s water in Lake Mead will help. Negotiations about the drought contingency plan will now move forward with greater certainty with the signing of Minute 323.

The final signatures for the Minute came from Roberto Salmón (Mexico) and Edward Drusina (U.S.). There were several officials from President Obama’s administration in attendance, including Jennifer Gimbel and Mike O’Connor. The negotiations started before last year’s election but did not conclude before the inauguration.

Minute 323 is an important piece of the puzzle for administering the Colorado River.

Central Colorado is joined at the economic hip with the Colorado River. A lot of transbasin water flows down the Arkansas River from the Twin Lakes and Fryingpan-Arkansas projects. Some is pumped over to South Park by Colorado Springs and Aurora but most of it goes down to Lake Pueblo and the Fry-Ark partners. Colorado Springs, Fountain and Security pump some back north in the Fountain Valley. Cities along the river divert and treat the water for their populations. The water also is used to grow the famous crops in the Arkansas Valley: Rocky Ford melons, Pueblo chile, corn and others. Timing the releases from Twin Lakes and Turquoise Reservoir also contributes to the rafting economy. 100 miles of the Arkansas River are designated as gold medal fisheries. Transbasin flows help the riparian habitat.

SHORT TAKES

• Comments about managing the Arkansas Headwaters Recreation Area are due by November 10, 2017. Check out the AHRA Plan Revision page on the Colorado Parks & Wildlife website.

• Congratulations to Wet Mountain Valley ranchers Randy and Claricy Rusk for winning the Dodge Award for a lifetime of conservation from the Palmer Land Trust.

• Congratulations to the Colorado Parks & Wildlife folks at the Roaring Judy Hatchery for successfully spawning the line of Cutthroat trout rescued from Hayden Creek during the Hayden Pass Fire.

• James Eklund has moved on from the Colorado Water Conservation Board and Becky Mitchell is the new director.

• Coloradans cam now legally collect rain off their roofs. Governor John Hickenlooper signed House Bill 1005 in May.

• R.I.P. Gary Bostrom. He was one of the driving forces behind Colorado Springs’ $825 million Southern Delivery System.

John Orr works for a Front Range water utility where he keeps one eye on the sky to monitor Colorado snowpack. He covers Colorado water issues at Coyote Gulch (www.coyotegulch.blog) and on Twitter @CoyoteGulch.

Martha Gomez-Sapiens, a monitoring team member and postdoctoral research associate in the UA Department of Geosciences, stands on a riverbank next to willows and cottonwoods that germinated as a result of the pulse flow. (Photo: Karl W. Flessa/UA Department of Geosciences)

Martha Gomez-Sapiens, a monitoring team member and postdoctoral research associate in the UA Department of Geosciences, stands on a riverbank next to willows and cottonwoods that germinated as a result of the pulse flow. (Photo: Karl W. Flessa/UA Department of Geosciences)

A group of scientists, including those from the U.S. Geological Survey, are also gaining insight into how the flow was felt by plants, animals and the overall delta ecosystem.

Using a mix of groundwater monitoring and satellite imagery, scientists say even the pulse’s modest flow of water — approximately one-twentieth the amount that spilled into the delta before humans built the river’s massive upstream dams — recharged aquifers, greened plant life and spurred the return of bird species.

Years before the flow, Mexico and the United States agreed to the experiment, and to the idea that the water was not just for human use, but can and should be used to revive ecosystems. The agreement — an update to a 1944 treaty between the two countries — gave Mexico the ability to store more water in American reservoirs and, just once, flood the final miles of the dry river bed to see what happened.

From above you can use the naked eye to see the water’s effect. Before and after photos show plant life greening not just in the river’s bed where water actually flowed, but beyond the banks, which Leenhouts says is a sign of recharged groundwater.

“In the two years following the flow it was possible to measure increased green up,” using satellite images, he says.

During that same period both the number of and varied species of birds increased, he says, a side effect of the revived vegetation.

Even though the pulse flow only lasted a few months in 2014, its effects lasted for years. The greenness of vegetation wasn’t as vibrant the following year, but it was still greener compared to 2013. That indicates the single sustained flow provided enough water to keep plants alive for at least a year…

Scientists’ chance to study and test the effect of simulated floods isn’t over. A new update to the 1944 treaty signed this year allows for more pulse flows when Mexico stores surplus water.

Colorado River pulse flow (Minute 319) reaches the Sea of Cortez for the first time since 1998 on May 15, 2014 via the Sonoran Institute

Here’s a report from Emily Benson writing for The High Country News. Click through and read the whole analysis. Here’s an excerpt:

For many people, the 2014 “pulse flow,” a large release of water from Morelos Dam, on the U.S.-Mexico border, was the defining feature of the 2012 agreement. The agreement also addressed drought, reservoir storage and environmental restoration in the Colorado River Delta. The 2014 release reunited the Colorado River with the Gulf of California for the first time since the late 1990s; it was both a scientific and symbolic success as communities along the Colorado River saw its dry channel once again fill with water. But the pulse flow also showed that a single release of water may not be the most efficient way to revitalize the Delta. So while the new agreement, called Minute 323, includes environmental water releases, it doesn’t specifically call for another pulse flow.

Since September 2015, the United States, the seven Colorado River Basin states, and key water users including CAWCD, have been working with their counterparts in Mexico to develop a successor agreement to Minute 319, now known as Minute 323.

The direct negotiations with Mexico included the Director of the Arizona Department of Water Resources (ADWR) representing the interests of Arizona. CAWCD staff participated in several work groups supporting the negotiation effort. The Minute was finalized by the Commissioners of the International Boundary and Water Commission in the United States and the Republic of Mexico on September 27, 2017.

The Minute provides significant and lasting benefits to water users in Mexico and the United States, including CAP water users. The Minute provides for new investments in water conservation infrastructure in Mexico which will make water uses in the Mexicali Valley more efficient for the long-term. Mexico and the U.S. agreed to share the risks of shortages and to share opportunities for surplus Colorado River water. In addition, Mexico agreed to participate in additional actions to protect Lake Mead, in the event that the U.S. water users implement a Drought Contingency Plan in the U.S. The new Minute is an extension and expansion of the collaborative and cooperative efforts to protect Lake Mead and sustain the shared resources of the Colorado River.

CAWCD has participated in the binational process between the United States and Mexico since 2008 to achieve four main goals, which have been included in Minute 323:

Decrease the duration or magnitude of shortages by seeking Mexico’s voluntary agreement to share in Colorado River shortages with U.S. water users.

Increase the storage in Lake Mead through the development and implementation of water conservation projects in Mexico.

Augment CAP water supplies through the implementation of conservation projects in Mexico and explore binational desalination projects to benefit Arizona and Mexico water users.

Manage salinity compliance operations so that river operational changes made as part of these agreements will not reduce Arizona’s return flows and thereby reduce CAP deliveries.

The key components on Minute 323 are:

Effective through 2026, consistent with the 2007 Guidelines.

Shortage is shared – if one country is in shortage, then the other country is in shortage with the same triggers that are identified for U.S. water users in the 2007 Guidelines; this is similar to Minute 319.

Surplus is shared – if one country can receive surplus, then the other country can receive surplus with the same initial trigger as U.S. water users as identified in the 2007 Guidelines; this is also similar to Minute 319.

Binational conservation projects have been expanded through the commitment to fund specified conservation projects in Mexico, to develop and fund additional projects, and to study binational desalination in the Gulf of California region.

Environmental flows and habitat restoration in the Colorado River delta region in Mexico will continue to be funded.

Salinity management projects will be expanded to improve the water quality of deliveries to Mexico while minimizing the impact to U.S. water users.

Binational Water Scarcity Contingency Plan has Mexico taking additional voluntary reductions upon the implementation of the Lower Basin Drought Contingency Plan, with the Mexico reductions similar to the Lower Basin states at the same elevation triggers.

In order to implement the Minute, a series of domestic agreements between U.S. parties were also executed. Overall, there are eight domestic agreements necessary to implement Minute 323 in Arizona and CAWCD is a party to six of these agreements, including a Memorandum of Agreement with ADWR. The CAWCD Board approved the execution of these agreements at the Board meeting on August 3, 2017. The domestic agreements were executed simultaneously with Minute 323. These agreements will serve to provide additional protection for CAP water users, and further CAWCD’s cooperative actions with its interstate and international partners to protect its Colorado River supply.

…a second round of releases is headed to the delta that won’t be nearly as dramatic [as the Minute 319 pulse flow]. But these flows will restore more riverfront with cottonwoods and willows than the last time and their impacts will likely last longer.

The new U.S.-Mexico Colorado River agreement, announced last week, sets aside 210,000 acre-feet of river water for environmental restoration in the delta over nine years, starting next year. This 2017 agreement also calls on the two countries to share shortages on the river in equal proportions in times of drought.

The earlier, 2012 agreement under which the huge pulse flow was unleashed also enabled the more gradual release of another 53,000 acre-feet over four years that will end Dec. 31, 2017.

The first round of flows has restored about 1,100 acres of cottonwood, willow and mesquite habitat, said Osvel Hinojosa, water and wetlands program director for Pro Natura Noroeste and a co-chair of an environmental working group that developed restoration ideas for the new agreement. Pro Natura is headquartered in Ensenada, Baja California.

In that time, more than 230,000 native cottonwoods and willows were planted along the river, said a coalition of six U.S. and Mexican conservation groups calling itself Raise the River. The groups raised more than $10 million for restoration work and to buy water rights for those releases.

This time, the goal is to restore about 4,300 acres over the next nine years, the new agreement says.

Now, “We will see a resurgence of the Colorado in its delta, the ribbon of green that is re-emerging in the Sonoran Desert,” said Jennifer Pitt of the National Audubon Society at last week’s signing ceremony in Santa Fe, New Mexico. “It offers relief to every living being that seeks rest in the cool shade of a cottonwood, renewal in the bounty of life that flows from the waters of the Colorado River. We are finding new ways to share the water, among our communities, but also with hundreds of thousands of egrets, herons, flycatchers, rails and other birds that need it to survive.”

Although smaller pulse flows may be released later, the immediate plan is to focus on lesser, steadier amounts of base flows, Hinojosa said. Pulse flows release lots of water over short periods from a single point such as the dam. Base flows deliver lesser amounts, often over longer periods to specific restoration sites.

“At this point, the best way to proceed with restoration is base flows. That’s the best use of the water,” said Karl Flessa, a University of Arizona geosciences professor who oversaw the scientific monitoring of the 2014 pulse-flow impacts and hopes to be involved in similar work this time.

A lot of the 2014 pulse flow infiltrated into deep groundwater and was not available to nourish cottonwoods and other trees, he said.

“By applying base flows to restoration sites, you make sure water gets to the right place at the right time,” Flessa said.

Hinojosa said he considers base and pulse flows equally valuable, and may want to use smaller pulse flows for social purposes — allowing people living nearby to enjoy water in the river and reconnect with nature.